A146439 Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1100-0100-0111 pattern in any orientation.

1, 1, 1, 1, 1, 1, 1, 1, 17, 17, 57, 57, 337, 337, 4357, 4357, 135183, 135183, 3521533, 3521533, 135176521, 135176521, 9933992919

Offset

1,9

Links

Table of n, a(n) for n=1..23.

Example

Maximal 9 X 9 example
.0.1.1.1.0.1.1.1.0
.0.1.0.0.0.0.0.1.0
.1.1.0.0.0.0.0.1.1
.0.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0.0
.1.1.0.0.0.0.0.1.1
.0.1.0.0.0.0.0.1.0
.0.1.1.1.0.1.1.1.0

Crossrefs

Sequence in context: A147133 A147164 A146692 * A146785 A146572 A147211

Adjacent sequences: A146436 A146437 A146438 * A146440 A146441 A146442

Keyword

nonn

Author

R. H. Hardin

Status

approved